Reversing-propeller.



0. A. BUWERS.

REVERSING PROPELLER.

APPLICATION FILED PER. 1?, 190a.

Patented J an. 26, 1909.

2 SHEETS-SHEET 1.

ZIEU?%7 rajoweus,

0. A. BOWBRS. REVBBBING PROPELLEB. AIPLIOATION FILED T13R17, 1908.

910,899. Patented Jan. 26, 1909. 2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

OLIVER A. BOWERS, OF MILFORD, MASSACHUSETTS, ASSIGNOR TO G. F. ROPER & COMPANY, OF HOPEDALE,MASSACHUSETTS, A FIRM.

BE VE RSING-PBOPE LLER.

To all whom it may concern:

Be it known that I, OLIVER A. Bownns, a citizen of the United States, and resident of Milford, county of Worcester, State of Massachusetts, have invented an Improvement in Reversing-Propellers, of which the following description, in connection with the accompanying drawing, is a specification, like letters on the drawing representing like parts.

This invention has for its cbjeot the production of a novel and eflicient two-bladed reversing propeller, so constructed and arranged that a substantially constant resistance or load is maintained on the motor irrespective of the osition of the blades.

The reversal in t e ropulsive effort of the pro ller is effected the propeller itself an without reversing the direct1on of rotation of the motor or requiring the assistance of intermediate gearing, the speed of the boat being also controlled by or through the propeller. United StatesPatent No. 807498 granted to (1- F. Roper December 19, 1905 shows and describes a four-bladed propeller having similar objects in view, but in utilizing a two-bladed propeller certain important changes in operation are necessary.

The constant resistance on the motor is effected by holding one of the two blades in one of its extreme positions while the opposite blade is moved from its corresponding position to the opposite extreme, and maintained in such posltion, after which the first blade is turned to its opposite extreme, the two blades then working to ether. Supposing the blades are set for ful s eed ahead, in reversing .one blade is turner to reverse position before the other blade starts, and the neutral position is attained, during which the boat stands still. The second blade is then turned to reverse position and both blades acting together the boat is propelled backward. An intermediate position between neutral and full speed ahead or astern will of course diminish the propulsive effort in one or the other direction and the boat will dtravel at a proportionately reduced spas A screw blade, that is, one which is of the same pitch at any distance from its center of rotation, and which consequently has a difl erent angularity at each of such points has more slant near the axis of rotation and on account of that fact it is desirable to turn the blades somewhat farther in reverse po Specification of Letters Patent.

Application filed February 1'7, 1908.

Patented Jan. 26, 1909 Serial N0. 416,199.

sition than they are turned when in forward position, in order that at neutral position the extra or additional angle of the reversed blade will compensate for the decreased an In of its central portion, balancin the pn l of the other blade in forward position.

The various novel features of construction embodied in my invention will be fully described in the subjoined specification and particularly pointed out in the following claims.

Figure 1 is a side elevation of a propeller embodying my invention, the motor shaft being broken oil and the manually-o erated means for changing the position of t e propeller blades being omitted as they may be of any suitable construction and form no part of my invention Fig. 2 is a sectional view on the line fi -t2, Fig. 1, looking toward the left, a portion of the casing being broken out Fig. 3 is a partial vertical section on the line 33, Fig. 4, only the ends of the casin being in section, Fig. 4 is a top plan view 0 the apparatus shown in Fig. 1, the blades being set for full speed ahead, the shaft being supposed to turn in the direction of the arrow thereon; Fig. 5 is a similar view but with the blades set in neutral position; Fig. 6 shows the apparatus in plan'with the blades set for full speed astern.

The driving or motor shaft 1 is extended loosely through a sleeve 2 which in practice is mounted rotatably and slidably in a suitable bcaring in the stern-post of the boat, substantiall as in the Roper patent referred to, and within the boat manually operated means will be provided to move the sleeve longitudinally of the shaft without interfering with its rotation. The shaft 1 is driven the motor at a constant speed and alwa s in the same direction. Near its outer end 1; shaft has secured to it a blade-carrying hub 23, fixed b a suitable set-screw 4, the hub having rigidly attached to or forming part of it two oppositely extended radial bearing pintles 5, preferably reduced in diameter at their outer ends, as at 6, (see dotted lines Fig. 3) the hub having flat bearing faces 7 at the base of and concentric with each pintle. I make no claim, however, to the articular construction of the pintles nor to t e fitting of the blades thereon, as the same is not of my invention.

Each of the two intles has mounted upon it a propeller ble 0 which is conveniently 66 but the location of the cam-slots herein is difmade as a castin having a heavy hub 8 9001(- eted to receive t e pintle, and a screw blade portion, and while both blades are alike I ave indicated them at 9 and 10 for convenience in reference. The blades are pivotall y mounted on the pintles and the ends of the blade-hubs 8 are each provided with a lateral foot 11 which rests upon the adjacent bearing face 7, the foot having near its outer end a pin or follower 12 arallel to the pintle and eccentric thereto, t 1e oppositely extended feet and their followers being shown in Fig. 2. The blades revolve with the shaft 1 but they can be turned about their own axes on the pintles 5, as will be clear, to change their angularity with respect to each other and to the axis of the shaft. To control the angularity of the blades, I inclose the hub 3 and the adjacent portions of the blades, and to retain the latter in place on the pintles I have provided a two-part combined controller and easing, consisting of the two shell-like members 13, 14, divided longitudinally and circular in cross-section but substantially elliptical in elevation, as shown. The ends 15 of the part 13 overlap the adjacent ends 16 of the art or member 14, the overlapped ends at t e inner extremity of the casing being screwed onto the threaded end of the sleeve 2, see Fig. 3, while a threaded bushing 17 is screwed into the overlapped ends at the outer extremity of the casing, thereby holding the two members thereof rigidly connected. This bushin 17 turns easily on the shaft 1 and is also 'reely slidable thereon when the casing is moved lon itudinally of the shaft to control and vary t e angularity of the two blades. Each member of the easing has a longitudinal and central slot 18 to loosely receive the blade hubs 8, the slots bein long enough to permit the full longitudina controlling movement of the casing.

As shown in Fig. 2 ,and also in Figs. 4, 5 and 6, the feet 11 of the two blades project from opposite sides of the blade hubs toward the sides of the casing members, and the enlarged ortion of each follower at the base of the huli 8 is held upon the seat 7 by the over- 1 'ing part 19 of the casing member, see

otted lines Fi 2. .The members of the casing have see a cam-slot of substantially L-shape, but said slots are in reversed position in the assembled casing, and relatively located as shown in Fi s. 4, 5 and 6, the lonitudinal ortions 20 o the slots lying paralel to the arge opening; 18, while the short transverse ortions or ends 21 are at right angles to t e openings 18, a follower 12 entermg each cam-slot.

In its general character the casing herein shown and described is substantiaily the same as is shown in United States Patent No. 878022, granted to C. F. Roper, Feb-ma 4, 1908, for a four-bladed reversing prope ler,

A, and to avoid confusion the blades 9 and 10 have not been shaded, the angles which the outer ends of the blades bear to each other being clearly shown by the full and dotted lines indicating such ends. When in full speed ahead position the follower 12 of the blade 9 is at the outer end of the short bend 21 of its cam-slot while the follower of blade 10 is at.the end of the longitudinal part 20 of its cam-slot, Fig. 4, and both followers are at the right of the intersection 22 of the lines 30 indicating the outer ends of the two blades.

To change the propeller blades to neutral position the controllin casing is moved toward the outer end of t e shaft 1 by longitudinal movement of the sleeve 2, and by such movement the blade 9 is turned, b the action of the bend 21 acting on the fo lower 12 of said blade, to its extreme opposite position, as shown in Fi 5. During such change the blade 10 is he d in its original position because its follower travels along the lon itudinal part 20 of its slot, so that the bla e 10 remains at full s eed ahead while the blade 9 hasl been set for ull speed astern, and the neutra stan s still as the propulsive effort of one blade is counterbalanced by the ropulsive effort of the other blade, but in t e o posite direc tion. This neutral state is in icated by the double-headed arrow N, Fig. 5. tion shown in said figure the crossing point of the outer edges of the blades, at 22, is located between the two followers 12, as is clearly apparent. Now b continuin the mb'veme'nt of the centre ler outwar blade 9 remains set, but as the follower of the blade 10 enters the bend 21 of its cam-slot the said blade is given an additional an ular movement, as shown in Fi 6, both b 'ades then being positioned for indicated by arrow B. The crossingpoint 22 of the outer edges of-the two blades is now wholly at the right of both of the followers 12. Inasmuch as a screw blade usual] has more slant near its axis of rotation found it desirable to turn the blades so that their outer edges are at a greater angle when they are in reversed position, Fig. 6, than when they are in forward position, Fi 4, so that at neutral of the then fu ly reversed blade, viz: t e blade 9 in Fi 5, will compensate for the decreased ang e of its central ortion and thereby balance the forward pul of the other blade 10. This increased angularity can be 12 wi seen in Figs. an be seen that the angle of the reversed blade 9 is greater than its angularity when set forwar as in Fi 4, and in Fig. 6 the a le be tween the two lades is greater than in ig. 4. 18

osition is maintained, when the boat In the posi- 10C the 10:

ll speed astern, 11(

have 111 osition the additiona an le 121 When in reversed osition, however, the blades are set proper y with relation to each other, each being set at the same angle with relation to the axis of the shaft 1, so that the two blades act with uniformity of effort.

It will understood from an inspection of the drawings that when chan ing from the position shown in Fig. 6 to t at shown in Fig. 4 the blade 10 wil be given its full movement angularly before the change in the angularity of the blade 9 is begun.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is 1. A shaft adapted to be rotated in one direction at a substantially uniform speed, a propeller mounted thereon comprising two oppositely located and angularly-movable b ades, and a single means to reverse the angularity of said blades and connected with both, said means operating to turn one blade to full reversed position while holdin the other blade in its original position and t ereafter turning the last-mentioned blade to its full reversed position While the first-named blade is maintained in full reversed position.

2. A ropeller having two 0 positely located b ades, and means, inclu ing a single member permanently connected with both blades, to vary the relative angularity of the blades from either extreme position to a neutral position, said means turning one blade to full reversed position while maintaining the angularity of the other blade unchanged.

3. In a reversing propeller, an larly movable screw blades, and means, inc uding a single member ernianently connected with both blades to c ange the angularity of the blades so that the angle between the blades at their outer ends is greater when said blades are in reverse 'position than when they are in their forward position, said means completelyreversing one blade before beginning the reversing movement of the other blade.

4. In a reversing ropeller, two angularly movable blades, and means including a single member permanentl connected with 0th blades to turn one lade to substantially full reverse position before the reversing movement of the other blade begins, whereby a substantially constant load is maintained on the motor.

5. A shaft adapted to be run in one direction at a substantially uniform speed, two oppositely extended and angularly movable propeller blades mounted thereon, and

means common to both blades, movable longitudinally of the shaft and operatively connected with said blades to turn one blade to full reversed position before beginning the reversing movement of the other blade, said means retaining the first-named blade in full reversed osition, while the movement of the-other blade is effected by said means.

6. A pro eller having two screw blades, in which one lade at extreme reverse osition neutralizes the effect of the other bla e at extreme forward position, and means includm a single member permanently connecte with both blades to control the position of the blades, said means reversing one blade before beginning the reversing movement of the other blade.

7. In a reversing propeller, two oppositely extended, angularly movable blades, and means to turn one blade from full forward position to full reversed position, and at a greater angle, before acting upon and be inning the reversing movement of the ot er blade, whereby at neutral position the greater angle of the reversed blade compensates for the decreased angle of its central portion, and balances the opposite pull of the other blade.

8. A shaft ada ted to be rotated in one direction, propeller lades mounted thereon and angularly movable about their own ,axes, and a single means to reverse completely the position of one of the blades and thereafter start and complete the reversal of the other blade and increase the angularity of the outer edges of the blades when in reversed position over such angularity when the blades are'in forward position, said means being permanently connected with both the blades.

9. It! a two-bladed reversing ropeller, in which .the blades are angular y movable, means, including a single controllin memher, to start the movement of one b ade to reverse position and substantially com lete such movement before the movement 0 the other blade begins, whereby a substantially constant resistance is maintained on the motor.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

OLIVER A. BOWERS.

Witnesses:

WALTER F. RoPER, EDWARD F. ALLEN. 

